[VHFcontesting] DEMI 222 help

[Bill Olson]

Ethan, the DEMI instruction manual for that transverter is online here it is for the "kit" version: vhflna doc (netsolhost.com)<http://01895fa.netsolhost.com/PDF/Manuals/222-28_677.PDF> This has all the info on the high power and low power IF drive options..

The M67712 is pretty robust.. I suspect it will be just fine when run at the output level you need for the Larcan..

bill, k1DY


________________________________
From: VHFcontesting <vhfcontesting-bounces+callbill=hotmail.com at contesting.com> on behalf of Ethan Miller K8GU <ethan at k8gu.com>
Sent: Wednesday, January 5, 2022 3:11 AM
To: VHF Contesting <vhfcontesting at contesting.com>; Midwest VHF/UHF Society Mailing List <mvus-list at lists.febo.com>
Subject: [VHFcontesting] DEMI 222 help

All,

I acquired an old DEMI 222-28 transverter from the K8CC estate last summer
and I'd like to get it rolling for the spring/summer contests (I have to
beam through "Mount Kettering" to get to the center of 222 Tuesday nights
from my home QTH and biggest amp I have for 222 is a 60-watt Larcan
pre-driver).

This unit has the M67712 hybrid as the PA and does not seem to match any of
the legacy schematics found on (the current) DEMI web site.  It's wired for
common-IF with what looks like an attenuator for high drive power.  Do I
need to know anything special about converting it to low-drive split-IF to
work with my K3 and K2 (and TS-930S)?  Or can I just remove the
attenuator/switching board and run coax straight from the rear panel
connectors to the RXIF and TXIF pads on the board?

Also, any experience or opinions about using the M67712-based transverter
on digital modes?  Muffin fan?  Low power?  Both?   I've been off the bands
above 6m the past couple of years since I moved from FM19 to EM79; but, if
my experience on 6m and the kvetching on the reflectors are any indication,
I'll need to spend some time on FT8.  I'm sure the Larcan pre-driver will
be fine at high duty cycle.

Thanks/73,

--Ethan, K8GU.


--
https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.k8gu.com%2F&data=04%7C01%7C%7C3bfbe71d726446156f9208d9cff9188e%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637769491037981918%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=%2FPIRuek1rp1milzVS93tsLDMIJ%2Fzm8fXCovoiSP1nHY%3D&reserved=0
Repair.  Re-use.  Re-purpose.  Recycle.
_______________________________________________
VHFcontesting mailing list
VHFcontesting at contesting.com
https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.contesting.com%2Fmailman%2Flistinfo%2Fvhfcontesting&data=04%7C01%7C%7C3bfbe71d726446156f9208d9cff9188e%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637769491037981918%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=drRKLkxJeLp6rY53Pal2v4gqdUc7ETFpep%2BT%2Ff7kd1U%3D&reserved=0